dumdumgreg

iTrader: (5)

For you turbo guys that have swapped in the 3.76 lsd form the Supra TT,
do you find that it takes ALOT longer to accelerate, cause the stock 5speed SC rear is like 4.08
is the ~.30 a big lag???

Gunnar

I hope it is. 4.08's with a decent sized single and gears go by pretty quickly.

Josh at FSM said the 3.76 is perfect for the 5-speed cars. The 3.26 is too far apart for a 5-speed but great for the 6-speed.

Bean

iTrader: (1)

yeah, with my first turbokit back in the day; 1st gear went by so fast, it built hardly any boost

Blizzy

iTrader: (-1)

The lower gearing from the 3.76 axle will make the engine work harder to accelerate when not in boost, increasing load on the engine. An increase in load will increase exhaust gas velocity and actually spool the turbocharger more quickly than the shorter gearing will.

A 4.08:1 axle with a 3.285:1 first gear ratio on the W58 results in an effective first gear ratio of 13.4:1. Most performance gurus say 10-12:1 is ideal for a street car. While the 13.4:1 will increase n/a performance and give the car a little added kick in the OEM n/a application (and prevent stall out with a motor that makes very little low end torque moving a heavy car), the lower 3.76:1 gearing is preferred in a turbocharged application.

Of course, there is a point of diminishing returns with the lowered gearing. You can go to the extreme and cause the engine to struggle too much out of boost; but, I properly stepped down rear end will actually increase boost response in terms of the rpm at which the engine will encounter boost, allowing for more boost to be built in every gear, achieveing an effectively wider power band as well.

I agree with Gunnar that the 3.76:1 rear axle is perfect for a turbo 5MT 2JZ. This results in an effective first gear ratio of 12.4:1, which is almost identical to the 12:1 first gear ratio that is present in the stock TT with the V160 (3.83:1 1st gear) and a 3.13:1 axle.

forcefed86

I like it.... My car cruises alot nicer on the highway now. I believe Im around 2300 @ 70.

Wish I had the 3.26's on my setup though. All depends on how much power you are gonna be making and what your setup is. I have a 3300 stall and an auto pushing 500 whp. So the 3.26's would suit me better. If anyone wants to trade some 3.26's let me know!

Will the 3.26 pumpkins even bolt into an auto sc300's rear axles/driveshaft?

Gunnar

Yeah, the 3.26 is from the 98+ SC400/GS400 I believe. Josh @ FSM has it in his car.

Blizzy

iTrader: (-1)

Agreed. I have four SC differentials in the garage right now in addition to the GS400 rear end. All have the same companion flange for the driveshaft.

PM Gazi (Aliga) for one. He may have one in stock, and he can get you a great price.